The parking cost at the local airport in dollars is C2175h1

The parking cost at the local airport (in dollars) is C=2+1.75(h-1) where h is the number of hours. for what range of hours is it parking cost between $37 and $51

Solution

The parking cost at the local airport (in dollars) is C=2+1.75(h-1) where h is the number of hours. for what range of hours is it parking cost between $37 and $51
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37 < 2 + 1.75(h-1) < 51
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Subtract 2 along the line to get:
35 < 1.75(h-1) < 49
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Divide thru by 1.75 to get:
20 < h-1 < 28
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Add 1 along the line
21 < h < 29
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